• The Journal of Advanced Prosthodontics
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• 제8권4호
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• pp.267-274
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• 2016

PURPOSE. This study aimed to evaluate the effect of surface treatments on bond strength of indirect composite material (Tescera Indirect Composite System) to monolithic zirconia (inCoris TZI). MATERIALS AND METHODS. Partially stabilized monolithic zirconia blocks were cut into with 2.0 mm thickness. Sintered zirconia specimens were divided into different surface treatment groups: no treatment (control), sandblasting, glaze layer & hydrofluoric acid application, and sandblasting + glaze layer & hydrofluoric acid application. The indirect composite material was applied to the surface of the monolithic zirconia specimens. Shear bond strength value of each specimen was evaluated after thermocycling. The fractured surface of each specimen was examined with a stereomicroscope and a scanning electron microscope to assess the failure types. The data were analyzed using one-way analysis of variance (ANOVA) and Tukey LSD tests (${\alpha}$=.05). RESULTS. Bond strength was significantly lower in untreated specimens than in sandblasted specimens (P<.05). No difference between the glaze layer and hydrofluoric acid application treated groups were observed. However, bond strength for these groups were significantly higher as compared with the other two groups (P<.05). CONCLUSION. Combined use of glaze layer & hydrofluoric acid application and silanization are reliable for strong and durable bonding between indirect composite material and monolithic zirconia.

• 대한치과교정학회지
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• 제40권1호
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• pp.27-33
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• 2010

성인 교정환자의 수요가 증가하면서 보철물 표면에 교정장치를 부착해야 하는 빈도가 늘어나고 있다. 본 연구는 금속표면에 교정장치를 직접 접착하고자 할 때 사용하는 metal primer와 silicoating으로 각각 금합금의 표면을 처리한 후 light emitting diode (LED) 광중합기를 사용하여 광중합을 시행하여 접착력을 평가해 보고자 하였다. Type III gold alloy 표면에 aluminum oxide를 이용한 sandblasting 후 4-META 계열의 metal primer로 처리한 시편과 silica를 이용한 sandblasting 후 silane으로 처리한 시편에 광중합형 접착레진인 Transbond XT를 이용하여 금속 브라켓을 접착하고 접착 후 1시간, 6시간, 24시간 후 전단접착강도의 변화를 비교, 관찰하였다. 측정된 값을 이원분산분석(two-way analysis of variance)을 이용하여 비교하고 두 가지 표면처리 방법 간에 접착강도에 차이가 있는지도 살펴보았다. 연구결과, metal primer에 비하여 silicoating을 시행한 시편에서 높은 전단접착강도가 관찰되었으며, 시간이 경과할수록 접착강도가 증가하는 경향을 보였다. Adhesive remnant index (ARI)에서는 군 간 유의한 차이를 보이지 않았다. LED를 이용하여 광중합을 시행하는 경우 법랑질에 비하여 긴 시간의 광중합을 실시하고 metal primer보다는 silicoating 방법을 사용하는 것이 금합금표면에 교정장치를 부착할 때 더 높은 접착강도를 얻을 수 있을 것이다.

• The Journal of Advanced Prosthodontics
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• 제12권2호
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• pp.75-82
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• 2020

PURPOSE. The aim of this study was to investigate the shear bond strength of luting cements used with implant retained restorations on to titanium specimens after different surface treatments. MATERIALS AND METHODS. One hundred twenty disc shaped specimens were used. They were divided into three groups considering the surface treatments (no treatment, sandblasting, and oxygen plasma treatment). Water contact angle of specimens were determined. The specimens were further divided into four subgroups (n=10) according to applied cement types: polycarboxylate cement (Adhesor Carbofine-AC), temporary zinc oxide free cement (Temporary CementZOC), non eugenol provisional cement for implant retained prosthesis (Premier Implant Cement-PI), and non eugenol acrylic-urethane polymer based provisional cement for implant luting (Cem Implant Cement-CI). Shear bond strength values were evaluated. Two-way ANOVA test and Regression analysis were used to statistical analyze the results. RESULTS. Overall shear bond strength values of luting cements defined in sandblasting groups were considerably higher than other surfaces (P<.05). The cements can be ranked as AC > CI > PI > ZOC according to shear bond strength values for all surface treatment groups (P<.05). Water contact angles of surface treatments (control, sandblasting, and plasma treatment group) were 76.17° ± 3.99, 110.45° ± 1.41, and 73.80° ± 4.79, respectively. Regression analysis revealed that correlation between the contact angle of different surfaces and shear bond strength was not strong (P>.05). CONCLUSION. The retentive strength findings of all luting cements were higher in sandblasting and oxygen plasma groups than in control groups. Oxygen plasma treatment can improve the adhesion ability of titanium surfaces without any mechanical damage to titanium structure.

• 대한치과보철학회지
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• 제48권4호
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• pp.251-258
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• 2010

연구 목적: 이 연구의 목적은 표면처리방법이 지르코니아와 네 종류의 시멘트의 전단결합 강도에 미치는 영향을 평가하는 것이다. 연구 재료 및 방법: 총 120개의 디스크 모양의 산화 지르코늄 (3Y-TZP, Kyoritsu, Tokyo, Japan) 시편을 다음과 같이 표면처리 하였다: (1) $110\;{\mu}m$ 산화 알루미나 분사처리 (2) Silica coating ($Rocatec^{TM}$ 3M ESPE)를 이용한 표면처리 (3) 처리하지 않음. 각각의 표면 처리 후, 2종의 자가 접착형 시멘트 (RelyX Unicem, Maxcem)와 레진 강화 글라스 아이오노머 시멘트 (RelyX Luting), Bis-GMA 레진 시멘트 (Nexus3)를 시편에 부착하였으며 각 군은 UTM을 이용하여 전단결합강도를 측정하였다. 표면처리, 시멘트의 종류에 따른 결합강도의 차이를 살펴보기 위하여 일원변량분석 (One-way ANOVA)과 이원변량분석 (two-way ANOVA)을 이용하고 사후 분석으로 Tukey HSD test를 실시하였다. 결과: 로카텍 처리 후, RelyX Unicem을 부착한 군이 가장 높은 결합 강도를 보였으며 (P<.05) 알루미나 분사처리를 한 군과 로카텍 처리를 한 군은 아무런 처리를 하지 않은 군보다 유의하게 높은 결합 강도를 보였다 (P<.05). 또한 모든 표면상태에서 RelyX Luting은 다른 군에 비해 통계적으로 유의하게 가장 낮은 결합강도를 보였다 (P<.05). 결론: 본 연구의 결과에 따르면 RelyX Unicem은 지르코니아와 강한 결합력을 보였으며 로카텍 처리는 결합을 증진시키는데 효과적이었다.

• Restorative Dentistry and Endodontics
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• 제38권4호
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• pp.241-247
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• 2013

Objectives: The aim of this study was to determine the effect of epigallocatechin gallate (EGCG) on the shear bond strength of composite resin to bleached enamel. Materials and Methods: Ninety enamel surfaces of maxillary incisors were randomly divided into 9 groups as follows: G1: control (no bleaching); G2: bleaching; G3: bleaching and storage for seven days; G4 - 6: bleaching and application of 600, 800 and 1,000 ${\mu}mol$ of EGCG-containing solution for 10 minutes, respectively; G7 - 9: bleaching and application of 600, 800 and 1,000 ${\mu}mol$ of EGCG-containing solution for 20 minutes, respectively. The specimens were bleached with 30% hydrogen peroxide gel and a composite resin cylinder was bonded on each specimen using a bonding agent. Shear bond strength of the samples were measured in MPa. Data was analyzed using the two-way ANOVA and Tukey HSD tests (${\alpha}$ = 0.05). Results: The maximum and minimum mean shear bond strength values were observed in G1 and G2, respectively. Time and concentration of EGCG showed no significant effects on bond strength of the groups (p > 0.05). Multiple comparison of groups did not reveal any significant differences between the groups except for G2 and all the other groups (p < 0.05). Conclusions: There is a significant decrease in bond strength of composite resin to enamel immediately after bleaching. A delay of one week before bonding and the use of EGCG increased bond strength of composite resin to bleached enamel.

• 한국소음진동공학회논문집
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• 제16권3호
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• pp.270-282
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• 2006

In general, the vertical vibration problems for strength of members and serviceability of building structures are not considered in structural design process, but the prediction of the vertical vibration is very important and essential to structural design process. This study aims to investigate the characteristics of vertical vibration in terms of the transfer of horizontal directions to near-rooms on the shear wall building structures. In order to examine the characteristics of vertical vibration, the modal test and the impact (heel-drop and hammer) excitation experiments were conducted several times on two building structure. The results from the experiments are analyzed and compared with the results. The results of this study suggest that the characteristics of vertical vibration transfer in horizontal way are effected from the fundamental frequency of the slabs, and are effected the shear wall on the Path of the vibration transfer.

• The Journal of Advanced Prosthodontics
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• 제9권5호
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• pp.350-357
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• 2017

PURPOSE. The object of the present study was to evaluate the shear bonding strength of composite to PEKK by applying several methods of surface treatment associated with various bonding materials. MATERIALS AND METHODS. One hundred and fifty PEKK specimens were assigned randomly to fifteen groups (n = 10) with the combination of three different surface treatments (95% sulfuric acid etching, airborne abrasion with $50{\mu}m$ alumina, and airborne abrasion with $110{\mu}m$ silica-coating alumina) and five different bonding materials (Luxatemp Glaze & Bond, Visio.link, All-Bond Universal, Single Bond Universal, and Monobond Plus with Heliobond). After surface treatment, surface roughness and contact angles were examined. Topography modifications after surface treatment were assessed with scanning electron microscopy. Resin composite was mounted on each specimen and then subjected to shear bond strength (SBS) test. SBS data were analyzed statistically using two-way ANOVA, and post-hoc Tukey's test (P<.05). RESULTS. Regardless of bonding materials, mechanical surface treatment groups yielded significantly higher shear bonding strength values than chemical surface treatment groups. Unlike other adhesives, MDP and silane containing self-etching universal adhesive (Single Bond Universal) showed an effective shear bonding strength regardless of surface treatment method. CONCLUSION. Mechanical surface treatment behaves better in terms of PEKK bonding. In addition, self-etching universal adhesive (Single Bond Universal) can be an alternative bonding material to PEKK irrespective of surface treatment method.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.469-474
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• 1998

To overcome the common deficiencies found in two-way slabs, such as excessive cracking around columns, excessive deflections and low punching shear strength, it was proposed to investigate the strategic use of steel fiber-reinforced concrete. Providing fiber-reinforced concrete results in an increase in the punching shear resistance, a significant increase in the ductility, greater post-cracking stiffness and better crack control.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2010년도 춘계 학술대회 제22권1호
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• pp.75-76
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• 2010

고성능 철근으로 휨 보강된 이방향 슬래브를 제작하고 펀칭 전단실험을 실시하였다. 휨철근의 항복강도, 휨 철근비 및 기둥 인접부 휨철근의 집중배근을 변수로 하여 실험하였고, 펀칭 전단강도, 균열후 강성, 변형률 분포, 균열제어 효과 등을 비교, 분석하였다.

• 구강회복응용과학지
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• 제35권2호
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• pp.72-80
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• 2019

목적: 본 연구의 목적은 레진계 치아고정 재료의 법랑질 치면 처리 방법에 따른 전단결합강도와 파절 양상을 비교 분석하는 것이다. 연구 재료 및 방법: 레진계 치아고정 재료로 G-FIX, LightFix를 사용하였다. 시편 제작을 위해 소의 하악 절치 20개를 사용했다. 노출된 법랑질 표면을 4부분으로 구분하여, 각 분획 마다 37% 인산(E), 37% 인산+Adhesive resin (E+A), 37% 인산+G-premio bond (E+GP), G-premio bond (GP)로 각각의 치면 처리를 하고, 재료를 접착하였다. 만능 시험기를 이용하여 전단결합강도를 측정하였고, 시편의 파절된 표면을 현미경으로 확대하여 파절 양상을 관찰하였다. Two-way ANOVA를 이용하여 재료와 표면처리 방법 사이의 상호작용을 검증하였고 각 재료에서 표면처리 방법 사이의 비교를 위해 One-Way ANOVA test를 하고 Scheffe's test로 사후 검정 하였다. 각 표면처리 방법에서 재료 사이의 전단결합강도를 비교하기 위해 independent t-test를 하였다. 모든 통계는 95% 유의수준에서 진행하였다. 결과: 동요치 고정을 위한 G-FIX는 산부식만 시행한 후 재료를 적용해도 접착 레진을 추가적으로 사용했을 때와 유사한 전단결합강도를 보였으며 LightFix는 산부식을 시행한 후 접착 레진을 추가적으로 사용했을 때 가장 높은 전단결합강도를 보였다. 또한, G-FIX와 LightFix 모두에서 별도의 산부식 없이 자가부식 접착제만 처리했을 때 가장 낮은 전단결합강도를 보였다. 교호작용의 검증 결과 치아고정용 레진과 표면처리 방법 사이의 상호 연관됨이 관찰되었다. 파절 양상은 모든 군에서 대부분 혼합성 파절이 관찰되었다. 결론: 치아 고정용 레진인 G-FIX와 LightFix의 사용시 제조사의 지시와 같이 산부식만 시행한 후 재료를 적용해도 충분한 접착이 이루어질 것으로 생각된다.